In an article published in the journal PNAS (https://www.pnas.org/content/118/5/e2022303118 ) by Matteo Baggioli, from School of Physics and Astronomy, SJTU and Alessio Zaccone of University of Milano, the law which governs the distribution of vibrational energy states of liquids, which has remained elusive and unsolved for over 100 years, has been derived mathematically for the first time combining the concept of instantaneous normal modes and the so-called Zeldovich regularization for unstable quantum states.

On 31st December 2020, Physical Review Letters published the research on granular statistical mechanics by Prof. Jie Zhang and his collaborator. The title of this paper is Friction-controlled Entropy-stability Competition in Granular Systems.

Granular system is defined as an assemble of macroscopic particles. Due to the lack of thermal fluctuations and existence of various dissipations, granular systems are recognized as typical non-equilibrium systems. Thus, how to apply traditional equilibrium statistical mechanics to granular systems has been a long-lasting puzzle in this field.